A seat is disclosed in US 2006/0055228 A1, in which U-shaped frames of various sizes may be folded out of the backrest. A seat is disclosed in DE 201 11 970 U1, in which a U-shaped frame may be pivoted out of the armrest such that it extends transversely to the armrest.
Seats are further known which in the child position are intended to transport a small child up to two years old in a reboard seat. In the child position, the reboard seat is moved into position so that the small child may be accommodated in the reboard seat counter to the normal seating direction. Reboard seats of this type are only suitable for small children. Children who are more than two years old may not be accommodated in a reboard seat.